This course is designed to provide a full overview of computer networking. We’ll cover everything from the fundamentals of modern networking technologies and protocols to an overview of the cloud to practical applications and network troubleshooting.
By the end of this course, you’ll be able to:
● describe computer networks in terms of a five-layer model.
● understand all of the standard protocols involved with TCP/IP communications.
● grasp powerful network troubleshooting tools and techniques.
● learn network services like DNS and DHCP that help make computer networks run.
● understand cloud computing, everything as a service, and cloud storage.

BC

I loved this course. When I had issues support was awesome sauce. I really enjoyed the puns this instructor used to keep you from going off in a daze. I really wish I would have found Coursera sooner.

II

Jun 12, 2018

Filled StarFilled StarFilled StarFilled StarFilled Star

Definitely teaches you the basic of networking that are needed to understand how it works as a whole. Would recommend anyone who is interested in learning about networking to enroll in this course.

レッスンから

The Network Layer

In the second week of this course, we'll explore the network layer in more depth. We'll learn about the IP addressing scheme and how subnetting works. We'll explore how encapsulation works and how protocols such as ARP allow different layers of the network to communicate. We'll also cover the basics of routing, routing protocols, and how the Internet works. By the end of this module, you'll be able to describe the IP addressing scheme, understand how subnetting works, perform binary math to describe subnets, and understand how the Internet works.

講師

Google

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Congrats! You now understand how both MAC addresses are used at the Data Link Layer and how IP addresses are used at the network layer. Now we need to discuss how these two separate addresses types relate to each other. This is where Address Resolution Protocol or ARP comes into play. ARP is a protocol used to discover the hardware address of a node with a certain IP address. Once an IP datagram has been fully formed, it needs to be encapsulated inside an Ethernet frame. This means, that the transmitting device needs a destination MAC address to complete the Ethernet frame header. Almost all network connected devices while retaining local ARP table. In ARP table is just a list of IP addresses and the MAC addresses associated with them. Let's say we want to send some data to the IP address 10.20.30.40. It might be the case that this destination doesn't have an entry in the ARP table. When this happens, the node that wants to send data sends a broadcast ARP message to the Mac broadcast address which is all EFHs. These kinds of broadcast ARP messages are delivered to all computers on the local network. When the network interface that's been assigned an IP of 10.20.30.40 receives this ARP broadcast, it sends back what's known as an ARP response. This response message will contain the MAC address for the network interface in question. Now, the transmitting computer knows what MAC address to put in the destination hardware address field and the Ethernet frame is ready for delivery. It will also likely store this IP address in its local ARP table so that it won't have to send an ARP broadcast the next time he needs to communicate with this IP. Handy. ARP table entries generally expire after a short amount of time to ensure changes in the network are accounted for. So don't expect it to stick around, the way I expect you to stick around for the next ungraded quiz.